Command reference

sfc /scannow

Verify protected Windows files and replace damaged copies when possible.

Syntax

sfc /scannow

Purpose: Compares protected system files with known copies in the Windows component store.
Administrator: Yes — open Terminal or Command Prompt as administrator.
Risk: Low, but repairs change protected files and the scan should not be interrupted.
Windows support: Windows 11 and Windows 10

When to use it

Several built-in Windows components malfunction
DISM has repaired the component store and protected files still need checking

When not to use it

Only one third-party application fails
Storage is physically unstable
As routine maintenance without a corruption symptom

Steps

Save work, use reliable power, and open an elevated terminal.
Run the command and allow Verification to reach 100%.
Read the final status. Restart if files were repaired, then retest the affected Windows component.

Expected result

SFC reports no integrity violations, successful repairs, or files it could not repair. The last outcome is not a successful repair.

Limitations

It does not repair third-party apps, ordinary user files, drivers, or hardware.
Some replacements require a healthy component store, which DISM can evaluate.